Engine exhaust after-treatment system

ABSTRACT

An engine exhaust after-treatment system is provided, which may include a particulate trap configured to remove at least some constituents of the exhaust flowing from an engine through an exhaust system. The system may also include a controller configured to collect in-service data related to an operating parameter indicative of the amount of time the engine operates. In addition, the system may include a memory device attached to the particulate trap and including a memory. The memory may be configured to store usage data indicative of how much time the particulate trap has been used in service. The memory may be configured to communicate with the controller to receive information related to the in-service data collected by the controller and update the usage data in the memory, based on the communication with the controller, to reflect a total amount of time the particulate trap has been in service.

This is a continuation of application Ser. No. 11/998,408, filed Nov.30, 2007 now U.S. Pat. No. 8,182,578 which is incorporated herein byreference.

TECHNICAL FIELD

The present disclosure is directed to an engine exhaust after-treatmentsystem and, more particularly, an engine exhaust after-treatment systemincluding a memory device configured to store usage data indicative ofhow much time the particulate trap has been used in service.

BACKGROUND

Engines, including diesel engines, gasoline engines, natural gasengines, and other engines known in the art, may exhaust a complexmixture of air pollutants. The air pollutants may include both gaseousand solid material, such as, for example, particulate matter.Particulate matter may include ash and unburned carbon particles and maysometimes be referred to as soot.

Due to, among other things, increased environmental concerns, exhaustemission standards have become more stringent. The amount of particulatematter and gaseous pollutants emitted from an engine may be regulateddepending on the type, size, and/or class of engine. In order to meetthese emissions standards, engine manufacturers have pursuedimprovements in several different types of engine technology, such asfuel injection, engine management, and air induction, to name a few. Inaddition, engine manufacturers have developed devices for treatment ofengine exhaust after it leaves the engine. This area of technology maybe referred to as after-treatment.

Engine manufacturers have employed exhaust treatment devices calledparticulate traps to remove the particulate matter from the exhaust flowof engines. Particulate traps may include a filter formed of a filtermaterial designed to trap particulate matter. The use of a particulatetrap for extended periods of time, however, may enable particulatematter (which includes soot and ash) to accumulate on the filter,thereby causing the filter to reduce in effective volume and resultingin a decline in engine performance.

One method of restoring the performance of a particulate trap mayinclude regeneration. Regeneration of a particulate trap filter systemmay be accomplished by thermal regeneration, which may includeincreasing the temperature of the filter and the trapped particulatematter above the oxidation temperature of the particulate matter,thereby burning away soot collected in the trap.

This increase in temperature may be effectuated by various means. Forexample, some systems employ a heating element (e.g., an electricheating element) to directly heat one or more portions of theparticulate trap (e.g., the filter material or the external housing).Other systems have been configured to heat the exhaust gases upstreamfrom the particulate trap, allowing the flow of the heated gases throughthe particulate trap to transfer heat to the particulate trap. Forexample, some systems may alter one or more engine operating parameters,such as air/fuel mixture, to produce exhaust gases with an elevatedtemperature. Running an engine with a “rich” air/fuel mixture canelevate exhaust gas temperature. Other systems heat the exhaust gasesupstream from the particulate trap, with the use of a burner thatcreates a flame within the exhaust conduit leading to the particulatetrap.

Nevertheless, even with regular regeneration, particulate traps mayperiodically require service, wherein a cleaning process is used toremove accumulated ash. Because the process of servicing a particulatetrap is not trivial and can take some time, the trap is often removedfrom the engine/vehicle for service and can be replaced with anothertrap to minimize downtime for the engine/vehicle.

The replacement traps are not necessarily new and are often previouslyused traps that have been serviced (i.e., cleaned). Particulate trapsmay lose some efficiency/performance over the course of their servicelife, such that, even after being serviced, the trap may not perform upto the same standard as when new.

Because of this degradation in performance, regulatory agencies mayrequire proof, or at least evidence, that any replacement particulatetrap installed on an engine/vehicle has not been in service for anylonger than the engine to which it is being connected. That is to saythat the regulatory agencies expect a certain amount of degradation inemissions performance of an engine and after-treatment system over time.Engines are “certified” by the regulatory agencies with theunderstanding that the performance will not degrade more than apredetermined amount. However, if a particulate trap that is older (interms of service life) than engine on which it is installed, the overallemissions performance may become substantially less efficient at thatstage of the engine system's life than was expected of a certifiedsystem.

Systems have been developed that monitor the service life of particulatetraps. For example, U.S. Patent Application Publication No.2006/0005534, issued to Wirth et al., discloses a particulate-filterservice-life determination unit. The system of the '534 publication,however, does not disclose a device that is specific to each particulatetrap, independent of the engine. Instead, the '534 publication disclosesthat the particulate-filter service-life determination unit is based ona system that measures exhaust parameters associated with theparticulate trap, such as pressure drop across the filter. That is, thesystem measures pressure drop across any filter installed in the exhaustsystem. Consequently, there is nothing tied to the particulate trap toindicate how long the trap has been in service. Thus, if the trap isremoved from the device, serviced, and then replaced, there is nothingto indicate how long it has been in service.

The present disclosure is directed at improvements in existing engineexhaust after-treatment systems.

SUMMARY

In one aspect, the present disclosure is directed to an engine exhaustafter-treatment system. The system may include a particulate trapconfigured to remove at least some constituents of the exhaust flowingfrom an engine through an exhaust system. The system may also include acontroller configured to collect in-service data related to an operatingparameter indicative of the amount of time the engine operates. Inaddition, the system may include a memory device associated with theparticulate trap and including a memory. The memory may be configured tostore usage data indicative of how much time the particulate trap hasbeen used in service. Further, the memory may be configured tocommunicate with the controller to receive information related to thein-service data collected by the controller and update the usage data inthe memory, based on the communication with the controller, to reflect atotal amount of time the particulate trap has been in service.

In another aspect, the present disclosure is directed to a method ofrecording the amount of time a particulate trap has been in service. Themethod may include collecting, with a controller, in-service datarelated to an operating parameter indicative of the amount of time anengine has been operated. The method may also include communicatinginformation related to the in-service data collected by the controllerfrom the controller to a memory device associated with a particulatetrap configured to remove at least some constituents of an exhaust flowfrom an engine through an exhaust system. In addition, the method mayinclude storing usage data on the memory device, based on thecommunication with the controller, wherein the usage data is indicativeof how much time the particulate trap has been used in service.

In another aspect, the present disclosure is directed to a memorydevice. The memory device may include a memory. The memory may beconfigured to store usage data indicative of how much time a particulatetrap has been used in service, the particulate trap being configured toremove at least some constituents of the exhaust flowing from an enginethrough an exhaust system. The memory may be further configured tocommunicate with a controller configured to collect in-service datarelated to an operating parameter indicative of the amount of time theengine operates in order to receive information related to thein-service data collected by the controller. In addition, the memory maybe configured to update the usage data in the memory, based on thecommunication with the controller, to reflect a total amount of time theparticulate trap has been in service.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic illustration of a machine having an engineexhaust after-treatment system according to an exemplary disclosedembodiment.

FIG. 2 is a block diagram representation of an exemplary engine andexhaust system including an exemplary disclosed after-treatment system.

DETAILED DESCRIPTION

Reference will now be made in detail to the drawings. Wherever possible,the same reference numbers will be used throughout the drawings to referto the same or like parts.

FIG. 1 illustrates a machine 10. Machine 10 may include, an engine 12and an exhaust system 14 configured to carry exhaust away from engine12. Although machine 10 is shown as a truck, machine 10 could be anytype of machine having an exhaust producing engine. Machine 10 mayembody a fixed or mobile machine that performs some type of operationassociated with an industry such as mining, construction, farming,transportation, or any other industry.

Examples of mobile versions of machine 10 may include vehicles, such asa road-going cars, trucks, and buses. Other such examples may includeoff-road vehicles, such as earth moving machines (e.g., excavators,dozers, loaders, backhoes, motor graders, dump trucks (as shown in FIG.1), or any other earth moving machine).

Examples of fixed versions of machine 10 may include power generationsets (e.g., gas turbine engines paired with electric power generators).Such power generation sets may be employed, for example, on off-shoreoil drilling rigs and ocean-going ships. In other embodiments, machine10 may, itself, be an ocean-going ship, powered by engine 12.

Engine 12 may be any kind of engine that produces an exhaust flow ofexhaust gases. For example, engine 12 may be an internal combustionengine, such as a gasoline engine, a diesel engine, a gaseous fuelburning engine (e.g., natural gas) or any other exhaust gas producingengine.

Exhaust system 14 may include an exhaust conduit 16 to which variouscomponents may be attached. For example, an engine exhaustafter-treatment system 18 may be associated with exhaust system 14 andmay be configured to treat the exhaust after the exhaust leaves engine12.

After-treatment system 18 may include one or more after-treatmentdevices. For example, after-treatment system 18 may include aparticulate trap 20, which may include a particulate filter material 22,and may be configured to remove at least some constituents of theexhaust flowing from engine 12 through exhaust system 14.

In addition, system 18 may also include a catalytic conversion unit 24.In some embodiments that are not shown, particulate trap 20 andcatalytic conversion unit 24 may be combined. For example, particulatetrap 20 and catalytic conversion unit 24 may be incorporated into asingle unit in a common housing. Further, in some embodiments,particulate filter material 22 may be formed from, or coated with, acatalytic material.

Particulate trap 20 may be configured to be thermally regenerated. Thatis, regeneration of particulate trap 20 may be accomplished byincreasing the temperature of particulate trap 20 above the combustiontemperature of the particulate matter collected therein.

Such increases in temperature of particulate trap 20 may be generated ina number of different ways. For example, heat may be directly applied toparticulate trap 20 via a heating device integral with or adjacent toparticulate trap 20. An example of such a heating device may include anelectric heating element (not shown). Alternatively or additionally, thetemperature of particulate trap 20 may be increased by heat transferredto it from the exhaust gases flowing through it. In such embodiments,heat may be applied to exhaust gases upstream from particulate trap 20.The temperature of the exhaust gases may be increased in one or moreways. For example, altering engine parameters may have an effect onexhaust gas temperature. Exhaust temperature may also be raised byheating the exhaust gases or exhaust conduit 16. For example, anelectric heating element and/or flame or plasma producing burner may beconfigured to heat the exhaust gases or exhaust conduit 16.

In some embodiments, after-treatment system 18 may include aregeneration device 26 configured to reduce an amount of particulatematter in particulate trap 20. For example, regeneration device 26 mayinclude a burner assembly configured to increase the temperature of theexhaust gases flowing through exhaust conduit 16 upstream fromparticulate trap 20. Regeneration device 26 may be configured tomaintain or restore the performance of particulate trap 20 throughthermal regeneration. Regeneration device 26 may be configured toprevent or restore any decline in engine performance and avoid possibledamage to particulate trap 20 by elevating the temperature ofparticulate trap 20, thus burning off particulate matter accumulatedtherein.

FIG. 2 is a block diagram representation of machine 10 includingafter-treatment system 18. As shown in FIG. 2, after-treatment system 18may also include a controller 28. Controller 28 may include any meansfor receiving information regarding machine operating parameters and/orfor monitoring, recording, storing, indexing, processing, and/orcommunicating such information. These means may include components suchas, for example, a memory, one or more data storage devices, a centralprocessing unit, or any other components that may be used to run anapplication.

Although aspects of the present disclosure may be described generally asbeing stored in memory, one skilled in the art will appreciate thatthese aspects can be stored on, or read from, types of computer programproducts or computer-readable media, such as computer chips andsecondary storage devices, including hard disks, floppy disks, opticalmedia, CD-ROM, or other forms of RAM or ROM. Various other knowncircuits may be associated with controller 28, such as power supplycircuitry, signal-conditioning circuitry, solenoid driver circuitry,communication circuitry, and other appropriate circuitry.

Controller 28 may perform multiple processing and controlling functions,such as, for example, engine management (e.g., controller 28 may includean engine control module, a.k.a. an ECM), monitoring of particulateloading, and controlling regeneration of particulate trap 20. Forexample, controller 28 may be configured to receive information fromsensors configured to collect data regarding operating parameters thatare indicative of the amount of particulate matter accumulated inparticulate trap 20. Controller 28 may be configured to activateregeneration device 26 in response to a determination, based on thecollected data, that the amount of material accumulated in particulatetrap 20 exceeds a predetermined amount.

Controller 28 may be configured to collect in-service data related to anoperating parameter indicative of the amount of time engine 12 operates.In some embodiments, the operating parameter may include, for example,distance traveled by a vehicle (e.g., machine 10) powered by engine 12.In other embodiments, the operating parameter may include, for example,the actual operating time of the engine.

In some embodiments, distance traveled may be used as a parameter forvehicles traveling substantial distances, e.g., road-going vehicles,such as passenger cars, hauling vehicles, etc. For these applications ofengines, the distance traveled by such vehicles may be indicative of theamount of time engine 12 operates. More specifically, distance traveledmay be indicative of the amount of time engine 12 operates under load,since on-road vehicles rarely put stress on their engines whilestationary.

In contrast, stationary machines (e.g., gas turbine powered generatorsets), or site construction machines (e.g., bulldozers, loaders, etc.)routinely tax their engines without traveling very far. Accordingly, forsuch machines, the operating parameter for which in-service data may becollected may include the actual operating time of engine 12. Thisparameter may sometimes be referred to as “engine hours” or “operatinghours.”

System 18 may include a display 30. Display 30 may be located at anysuitable location on machine 10, such as, for example, at an operatorstation (e.g., on a dashboard). Display 30 may be any kind of display,including screen displays, such as, for example, cathode ray tubes(CRTs), liquid crystal displays (LCDs), plasma screens, and the like.

Display 30 may be configured to display information about operatingparameters of system 18. For example, display 30 may include a warningindicator 32 (e.g., a warning lamp, warning message, etc.). Controller28 may be configured to illuminate warning indicator 32 upon detectionof the predetermined amount of faults. As an alternative or in additionto display 30, system 16 may include one or more audible alerts forconveying information about operating parameters of system 16 to anoperator.

In addition to providing visual feedback regarding operating parametersof system 18, display 30 may also be configured to display otherinformation regarding system 18 or any other device and/or systemassociated with work machine 10. For example, display 30 may also beconfigured to indicate when a regeneration event is occurring or aboutto occur.

After-treatment system 18 may include a memory device 34 associated withparticulate trap 20. In some embodiments, the memory device may befixed, or otherwise attached, to particulate trap 20 in any suitable way(e.g., bolts, screws, adhesive, welding, etc.). Memory device 34 mayinclude a memory 36 configured to store usage data indicative of howmuch time particulate trap 20 has been used in service. Memory 36 may befurther configured to communicate with controller 28 to receiveinformation related to the in-service data collected by controller 28.In some embodiments, memory 36 and controller 28 may be configured tocommunicate via a wireless network (e.g., with radio frequencytransmission). Alternatively, memory device 34 may be connectable tocontroller 28 with an appropriate, removable wire connector.

In some embodiments memory device 34 and controller 28 may communicatevia an industry standard communication network, such as, for example,Controller Area Network (a.k.a., CAN or SAE J1939), Local InterconnectNetwork (LIN), or FlexRay. Also, in some embodiments, memory 36 may beflashable.

In addition, memory 36 may be configured to update the usage data inmemory 36, based on the communication with controller 28, to reflect atotal amount of time particulate trap 20 has been in service. In someembodiments, the information received by memory device 34 may includethe in-service data collected by controller 28.

In some embodiments, communication of information from controller 28 tomemory device 34 may be performed continually, in real-time. Forpurposes of this disclosure, the term “real-time” shall refer to theimmediate or substantially immediate availability of data, e.g., asengine operation time elapses and/or as the distance traveledincrementally climbs. That is, in-service data may be available forconsideration, with respect to the communication between memory device34 and controller 28, as quickly as the data can be collected bycontroller 28. Such availability may be virtually instantaneous or maytake a few seconds or minutes to complete. In such embodiments, memorydevice 34 may include an incremental time counter that counts as long asthe engine to which it is attached is running. For example, in oneembodiment, memory device 34 may continue to increment the counter aslong as the engine rpm data in controller 28 is above a predeterminedamount (e.g., several hundred rpm below idle).

In other embodiments, the communication of information from controller28 to memory device 34 may be performed periodically, at a predeterminedtime interval. For example, for every hour of engine operation recordedby controller 28, controller 28 may communicate with memory device 34 toupdate the data log therein.

In still other embodiments, the communication of information fromcontroller 28 to memory device 34 may be performed upon shutdown ofengine 12. In such embodiments, upon shutdown, the length of time theengine was operated since it was last turned on may be communicated tomemory device 34, or otherwise influence the incremental increase inin-service hours stored in memory device 34.

In some embodiments, controller 28 may be further configured to retrieveinformation from memory device 34 to determine the total amount of timeparticulate trap 20 has been in service. Controller 28 may be configuredto generate a fault if the total amount of time the particulate trap hasbeen in service exceeds the total amount of time the engine has beenoperated. Controller 28 may also be configured to prevent operation ofengine 12 if a fault is generated. In addition, controller 28 may beconfigured to display an alert and/or information about such a faultusing display 30, e.g., with warning indicator 32. In some embodiments,comparisons between total in-service time of engine 12 and totalin-service time stored in memory 36 on particulate trap 20 may be madecontinually, e.g., in real time. In other embodiments, the comparisonsmay be made periodically. Periodic comparisons may be made on demand(i.e., by a user) in some embodiments.

In addition, these comparisons may be used to confirm that the timecounters in memory device 34 and controller 28 do not become slightlyout of synch. If the counts become moderately divergent, system 10 maybe configured to correct, i.e., synchronize, the counts in the twocomponents.

In addition to the data handling capabilities described above, memorydevice 34 may also be configured to withstand elevated temperaturesexperienced by particulate trap 20. Besides the high temperatures ofexhaust gases produced by engine 12, particulate trap 20 may also besubjected to even higher temperatures during thermal regenerationprocesses, as described above. Memory device 34 and other data handlinghardware associated with memory device 34 may be insulated or otherwiseconfigured to withstand these temperatures.

INDUSTRIAL APPLICABILITY

The disclosed after-treatment system may be applicable to anyapplication of an exhaust producing engine. The disclosed system mayfacilitate monitoring and ensuring that replacement after-treatmentsystem componentry performs on par with the remainder of theafter-treatment system. In some embodiments, the disclosed system mayensure that after-treatment devices, such as particulate traps, are noolder, in terms of a total amount of use, than the engine to which theafter-treatment system is attached.

Further, while system 10 and memory device 34 are discussed above withrespect to use for monitoring the service life of particulate traps,memory device 34 and system 10 may also be used to monitor the servicelife of any after-treatment component. For example, system 10 may alsobe used to monitor service life of catalyst-based devices, such asSelective Catalytic Reduction (SCR) catalysts, Diesel OxidationCatalysts (DOC), etc.

An exemplary method of using the disclosed system is discussed below.The following is a discussion of an exemplary method of recording theamount of time a particulate trap has been in service.

The method may include collecting, with a controller, in-service datarelated to an operating parameter indicative of the amount of time anengine has been operated. The method may also include communicatinginformation related to the in-service data collected by the controllerfrom the controller to a memory device associated with a particulatetrap configured to remove at least some constituents of an exhaust flowfrom an engine through an exhaust system. In addition, the method mayinclude storing usage data on the memory device, based on thecommunication with the controller, wherein the usage data is indicativeof how much time the particulate trap has been used in service.

In some embodiments, the communication of information from thecontroller to the memory device may be performed continually, inreal-time. In other embodiments, the communication of information fromthe controller to the memory device may be performed periodically, at apredetermined time interval. Alternatively, the communication ofinformation from the controller to the memory device may be performedupon shutdown of the engine. In such an embodiment, the length of timethe engine was operated since it was last turned on may be communicatedto the memory device.

The exemplary method may further include retrieving information with thecontroller from the memory device to determine the total amount of timethe particulate trap has been in service and generating a fault with thecontroller if the total amount of time the particulate trap has been inservice exceeds the total amount of time the engine has been operated.In addition, the method may include preventing operation of the engineif the fault is generated.

It will be apparent to those having ordinary skill in the art thatvarious modifications and variations can be made to the disclosed engineexhaust after-treatment system without departing from the scope of theinvention. Other embodiments of the invention will be apparent to thosehaving ordinary skill in the art from consideration of the specificationand practice of the invention disclosed herein. It is intended that thespecification and examples be considered as exemplary only, with a truescope of the invention being indicated by the following claims and theirequivalents.

1. An engine exhaust after-treatment system comprising: an engineconfigured to produce an exhaust; a particulate trap connected to theengine to direct the exhaust therethrough, the particulate trapincluding a memory device configured to store data indicative ofparticulate trap service life, the particulate trap service life being atotal length of time the particulate trap has been used in serviceconnected to any engine; and a controller operably coupled to theengine, the controller being configured to: store data indicative ofengine service life, the engine service life being a total length oftime the engine has been used in service; and identify, based on theparticulate trap service life and the engine service life, whether theparticulate trap has been used in service for a longer time than theengine to which the particulate trap is coupled.
 2. The system of claim1, wherein the memory device is operably coupled to the particulatetrap.
 3. The system of claim 2, wherein the memory device is fixed tothe particulate trap.
 4. The system of claim 1, wherein the memorydevice is configured to communicate with the controller and update theparticulate trap service life stored in the memory device based on anincrease in the engine service life.
 5. The system of claim 4, whereinthe memory device is configured to communicate wirelessly with thecontroller.
 6. The system of claim 4, wherein the memory device isconfigured to communicate with the controller through a wiredconnection.
 7. The system of claim 1, wherein the controller isconfigured to display an alert if the particulate trap has been used inservice for a longer time than the engine to which the particulate trapis coupled.
 8. The system of claim 1, wherein the controller isconfigured to prevent operation of the engine if the particulate traphas been used in service for a longer time than the engine to which theparticulate trap is coupled.
 9. The system of claim 1, wherein theparticulate trap service life stored in the memory device includes alength of time the particulate trap has been used in service in anengine different from the engine to which the particulate trap iscoupled.
 10. The system of claim 9, wherein the particulate trap servicelife additionally includes identifying a length of time the particulatetrap has been used in service in the engine to which the particulatetrap is coupled.
 11. A particulate trap configured to filter exhaustfrom an engine, the particulate trap comprising: a memory device fixedto the particulate trap, the memory device being configured to storedata indicative of particulate trap service life, the particulate trapservice life being a total amount of time the particulate trap has beenpreviously used in service, wherein the data stored in the memory deviceincludes a length of time the particulate trap has been used in servicein an engine different from the engine that the particulate trap isinstalled on.
 12. The particulate trap of claim 11, wherein the memorydevice is configured to communicate with a controller of an engine thatthe particulate trap is installed on to update the data stored in thememory device.
 13. The particulate trap of claim 12, wherein the memorydevice is configured to communicate with the controller wirelessly. 14.A method of detecting if a particulate trap installed in an engine hasbeen used in service for a longer time than the engine has been used inservice, the method comprising: storing data indicative of particulatetrap service life in a memory device associated with the particulatetrap, the particulate trap service life including an amount of time theparticulate trap has been used in service prior to installation in theengine; recording data indicative of engine service life in a controllerof the engine, the engine service life being indicative of an amount oftime the engine has been used in service; and detecting, based on thestored data indicative of particulate trap service life and the recordeddata indicative of engine service life, if the particulate trapinstalled in the engine has been used in service for a longer time thanthe engine has been used in service.
 15. The method of claim 14, whereinthe storing includes updating the stored data indicative of particulatetrap service life using the recorded data indicative of the engineservice life.
 16. The method of claim 15, wherein the updating includescommunicating the recorded data indicative of engine service life to thememory device associated with the particulate trap.
 17. The method ofclaim 16, wherein the communicating includes transmitting the dataindicative of engine service life wirelessly to the memory device. 18.The method of claim 14, further including preventing operation of theengine if the particulate trap installed in the engine has been used inservice for a longer time than the engine has been used in service. 19.The method of claim 14, further including displaying an alert if theparticulate trap installed in the engine has been used in service for alonger time than the engine has been used in service.
 20. A memorydevice configured to be used in an exhaust system of an engine includinga particulate trap, comprising: a memory configured to store dataindicative of a total length of time the particulate trap has been usedin service prior to installation in the engine, and communicate with acontroller of the engine to update the data stored in the memory device.21. The memory device of claim 20, wherein the memory is configured tostore data indicative of a length of time the particulate trap has beenused in service in an engine different from the engine that theparticulate trap is installed on.
 22. The memory device of claim 20,wherein the memory device is configured to be physically attached to theparticulate trap.